To record only the audio you really want to use, place the microphone as close to the subject as possible.

All microphones work in the same basic way—each has an object or device that vibrates when audio waves reach it and a method for translating those vibrations into an electronic signal. The electronic signal is then moved through a wire and stored on some type of recording media.

Sound is created by vibrating objects. The vibrations disturb the air molecules around the object, which in turn disturbs the air molecules next to them. This creates an audio wave that travels through the air.

The wave attributes that are important to understand are wavelength, frequency, and amplitude.

Frequency is measured in hertz (Hz), while amplitude is measured in decibels (dB).

Digital audio is created by sampling, much the same way as digital video is created from analog video. Bit depth determines how close each sample can get to the original signal. DV audio is 16 bit 44.1 kHz.

All microphones work in the same basic way. First, an element, usually a diaphragm, vibrates with the audio waves. The vibrations create an electrical current that is sent to some type of a storage device.

The three most common types of microphones are dynamic, condenser, and ribbon.

Each microphone has an area around it that is sensitive to sound called a pickup pattern.

Microphones can be camera mounted, handheld, boom, or lavalier.

The four commonly used audio connectors are RCA, mini, XLR, and telephone. RCA and mini are unbalanced, while XLR and telephone connectors are balanced.

Wireless systems consist of a transmitter connected to the microphone and a receiver connected to the camera.

Headphones, field mixers, and portable recorders are other pieces of equipment you might want to have.

People are the key to acquiring good audio. Scouting locations at the same time that a shoot is scheduled, listening while your eyes are closed, and having somebody focusing solely on audio helps make sure that the audio is as good as possible.